Status and phase
Conditions
Treatments
About
Despite advances in treatment and corresponding improvements in survival, patients with pulmonary arterial hypertension (PAH) remain highly symptomatic. In one survey of 315 patients with PAH, sixty-eight percent had moderate or severe dyspnea on exertion and 40% had a profound and clinically significant deficit in quality of life. Palliative care is being increasingly investigated in life-limiting cardiovascular diseases to alleviate symptoms. In PAH, its implementation is frequently delayed until end-of-life. Opioids are a common palliative care intervention, however the efficacy and safety of opioids for symptom relief in PAH has not been evaluated.
Full description
There is biologic plausibility for opioids in the treatment of dyspnea in PAH. Opioids have widespread effects including venodilation, vasodilation, reducing sympathetic outflow, blunting hypercapnic and hypoxic ventilatory responses, and altering the central perception of dyspnea. Although the origins of dyspnea in PAH are incompletely understood and multifactorial, right ventricular dysfunction reduces exercise capacity and likely also plays a role in the development of dyspnea. Mechanoreceptors situated in the right atrium and right ventricle sense elevated pressures and via sympathetic afferents may lead to an augmentation of ventilatory response and hence dyspnea. Morphine may specifically antagonize this feedback loop by causing venodilation and blunting sympathetics. Morphine also reduces central chemosensitivity and perceptions of dyspnea. Therefore, the drug may antagonize both peripheral and central drivers of dyspnea in PAH.
Investigators will conduct a single-center feasibility study of morphine for treatment of dyspnea and exercise intolerance in PAH. Participants will complete two 6-minute walk tests (6MWT) within one week. Participants will be randomly assigned to receive morphine prior to either the first or second 6MWT. Symptoms and 6-minute walk distance (6MWD) will be compared between the two tests.
Enrollment
Sex
Ages
Volunteers
Inclusion criteria
Aged 18 or older
Diagnosis of Group 1 pulmonary hypertension including idiopathic PAH, heritable PAH, and PAH that is drug- or toxin-induced, associated with connective tissue disease, human immunodeficiency virus (HIV) infection, congenital heart disease, or schistosomiasis23
PAH confirmed by means of a right heart catheterization demonstrating:24
World Health Organization (WHO) Functional Class III or ambulatory Class IV
Six-minute walk test performed within the past 6 months demonstrating a distance of at least 50 metres.
Unchanged PAH medication regimen for 30 days prior to enrolment. Therapy may include endothelin-receptor antagonists, phosphodiesterase type 5 inhibitors, soluble guanylate cyclase stimulators, or oral or parenteral prostacyclin analogues. Diuretic doses may change.
Exclusion criteria
Primary purpose
Allocation
Interventional model
Masking
15 participants in 2 patient groups
Loading...
Data sourced from clinicaltrials.gov
Clinical trials
Research sites
Resources
Legal